/*
 * Copyright 2012-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package samples.websocket.tomcat.snake;

import java.awt.Color;
import java.util.Iterator;
import java.util.Random;
import java.util.concurrent.atomic.AtomicInteger;

import org.springframework.stereotype.Component;
import org.springframework.web.socket.CloseStatus;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.handler.TextWebSocketHandler;

@Component
public class SnakeWebSocketHandler extends TextWebSocketHandler
{
    
    private static final AtomicInteger snakeIds = new AtomicInteger(0);
    
    private static final Random random = new Random();
    
    private final int id;
    
    private Snake snake;
    
    public static String getRandomHexColor()
    {
        float hue = random.nextFloat();
        // sat between 0.1 and 0.3
        float saturation = (random.nextInt(2000) + 1000) / 10000f;
        float luminance = 0.9f;
        Color color = Color.getHSBColor(hue, saturation, luminance);
        return '#' + Integer.toHexString((color.getRGB() & 0xffffff) | 0x1000000).substring(1);
    }
    
    public static Location getRandomLocation()
    {
        int x = roundByGridSize(random.nextInt(SnakeUtils.PLAYFIELD_WIDTH));
        int y = roundByGridSize(random.nextInt(SnakeUtils.PLAYFIELD_HEIGHT));
        return new Location(x, y);
    }
    
    private static int roundByGridSize(int value)
    {
        value = value + (SnakeUtils.GRID_SIZE / 2);
        value = value / SnakeUtils.GRID_SIZE;
        value = value * SnakeUtils.GRID_SIZE;
        return value;
    }
    
    public SnakeWebSocketHandler()
    {
        this.id = snakeIds.getAndIncrement();
    }
    
    @Override
    public void afterConnectionEstablished(WebSocketSession session)
        throws Exception
    {
        this.snake = new Snake(this.id, session);
        SnakeTimer.addSnake(this.snake);
        StringBuilder sb = new StringBuilder();
        for (Iterator<Snake> iterator = SnakeTimer.getSnakes().iterator(); iterator.hasNext();)
        {
            Snake snake = iterator.next();
            sb.append(String.format("{id: %d, color: '%s'}", Integer.valueOf(snake.getId()), snake.getHexColor()));
            if (iterator.hasNext())
            {
                sb.append(',');
            }
        }
        SnakeTimer.broadcast(String.format("{'type': 'join','data':[%s]}", sb.toString()));
    }
    
    @Override
    protected void handleTextMessage(WebSocketSession session, TextMessage message)
        throws Exception
    {
        String payload = message.getPayload();
        if ("west".equals(payload))
        {
            this.snake.setDirection(Direction.WEST);
        }
        else if ("north".equals(payload))
        {
            this.snake.setDirection(Direction.NORTH);
        }
        else if ("east".equals(payload))
        {
            this.snake.setDirection(Direction.EAST);
        }
        else if ("south".equals(payload))
        {
            this.snake.setDirection(Direction.SOUTH);
        }
    }
    
    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus status)
        throws Exception
    {
        SnakeTimer.removeSnake(this.snake);
        SnakeTimer.broadcast(String.format("{'type': 'leave', 'id': %d}", Integer.valueOf(this.id)));
    }
    
}
